It was a common practice in the prior art to blend siloxane compounds in silicone resins for imparting adhesion to the silicone resins. For example, Japanese Patent Application Kokai Nos. 47605/1987, 47608/1987 and 49305/1987 disclose hydrogensiloxanes having a perfluoropolyether group or perfluoroalkylene group in a backbone and at least two SiH groups in a molecule. They are of the following formula (5). ##STR1## In the formula, Rf is a perfluoropolyether group or perfluoroalkylene group and p is equal to 1, 2 or 3. These siloxane compounds are, however, difficult to impart sufficient adhesion to fluorinated silicone resins. There is a need for the development of siloxane compounds capable of imparting sufficient adhesion to fluorinated silicone resins too.